"Realistic goals – that's where people fall down so many times," said Frank Farley, a professor of educational psychology at Temple University in Philadelphia.

"You've got to keep your goals realistic, few in number, very specific and simple," he said. "So, you know, a thing like no fries, no ice cream for two months. That's very straightforward, it's simple, it's few in number. If you work at that and you stick with it, you're building a new habit."

New year = fresh start

The reason why the new year is a popular time for resolutions is that people see it as a fresh start, according to Anne Wilson, a psychology professor at Wilfrid Laurier University in Waterloo, Ont., and a Canada research chair in social psychology.

Anne Wilson is a psychology professor at Wilfrid Laurier University in Waterloo, Ont. (wlu.ca)

The beginning of the year is also seen as a time to make a change or to try succeeding where someone has failed before.

"People have self-improvement goals, I think, at almost any time of the year," she said, "but part of the reason why there's this special cluster around the new year is because the new year's really this symbolic fresh start for a lot of people, and one of the things that this fresh start does is allow people to move past failures."

"Some people really feel tied to those past failures," she added. "They see those past failures as something … it's like it's information that tells them that they're probably not going to be able to succeed the next time. So what a fresh start does [is] it allows them to kind of leave that behind and then start again."

The key is resolve

Farley laid out an easy way for people to think about resolutions, using the world resolve:

Realistic goals.

Evaluate your progress. "Stay on top of it along the way," he said.

Share your plans with others.

Optimism. "Don't go into this thing on New Year's pessimistic," he said. "Go in optimistic – a positive, can-do attitude."

Lists will help you keep organized about what you're doing, where to do it and when.

Value what you're doing. "Give your resolution some priority in your life and reward yourself along the way when you stick to your resolution," he said.

Embrace change.

Planning to save more money in 2017? Make your goals realistic and have a plan in place to make it happen, Temple University professor Frank Farley says. (Getty Images)

Don't pin it all on Jan. 1

Wilson encouraged people to really think about their goals, decide what they want to do and then pick a starting date that works for them.

"If the reason that you're starting a New Year's resolution is simply because of the cultural expectation to do that, it might not be the time for you to do it if it's not really a goal you care about personally," she said.

"There's actually evidence that people tend to engage in this through the year. So, at the beginning of every month, you have a tendency for people to have this up tick in their goal pursuit. Even the beginning of every week – so a Monday can be a sort of mini fresh start. People do the same thing around their birthday."

Failure is OK

Part of embracing change includes accepting failure as part of the process, Wilson said.

"People have very different mindsets about what a failure means. So, for one person, a failure is really an indication that, 'No, this isn't something I can do.' But other people actually believe that the self is really a work in progress," Wilson said.

If the reason that you're starting a new year's resolution is simply because of the cultural expectation to do that, it might not be the time for you to do it.- Anne Wilson, psychology professor at Wilfrid Laurier University

People who have the latter mindset don't need it to be the new year to make a change, she added. They see failure as part of the process and they learn from it to continue to work towards their goal.

"If somebody's encountered a failure, it's a really good time to remind them that failures can actually be a piece of information to help you succeed the next time and that everybody is changeable and that this doesn't mean that you're not capable of doing something," she said.

"When people are reminded of these different ways of seeing the world during times when they've failed, those are times when it's really especially likely that they'll change their mindset towards something else."